Nvis 5586A
Nvis Technologies Pvt. Ltd.
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The 8086 Addressing Modes
Addressing mode indicates a way of locating data or operands. The addressing modes
describe the types of operands and the way they are accessed for executing an instruction.
1.
Immediate Addressing Mode:
In this addressing mode, the data is provided in the
instruction.
Example: MOV AX, 0006H
2.
Direct Addressing Mode:
In this addressing mode, the instruction operand specifies the
memory address where data is located.
Example: MOV AX, [7000H]
3.
Register Addressing Mode:
In this addressing mode, the data is stored in a register and
it is referred using the particular register. All the registers, except IP, may be used in this
mode.
Example: MOV BX, AX
4.
Register indirect Addressing Mode:
In this addressing mode, the offset address of data
is in either BX or SI or DI registers. The default segment is either DS or ES.
Example: MOV AX, [BX]
Here data is present in a memory location in DS whose offset address is in BX.
5.
Register Relative Addressing Mode:
In this addressing mode, the data is available at an
effective address formed by adding an 8-bit or 16-bit displacement with the content of
any one of the registers BX, BP, SI and DI in the default (either DS or ES) segment.
Example: MOV AX, 50H [BX]
6.
Indexed Addressing Mode:
In this addressing mode, the offset of the operand is stored
in one of the index registers. DS and ES are the default segments for index registers SI
and DI respectively. 8-bit or 16-bit instruction operand is added to the contents of an
index register (SI or DI), the resulting value is a pointer to location where data resides.
Example: MOV AX, [SI]
7.
Based Indexed Addressing Mode:
In this addressing mode, the effective address of data
is formed by adding content of a base register (any one of BX or BP) to the content of an
index register (any one of SI or DI), the resulting value is a pointer to location where
data resides. The default segment register may be ES or DS.
Example: MOV AX, [BX] [SI]
8.
Relative
Based Indexed Addressing Mode:
The effective address is formed by adding
an 8-bit or 16-bit displacement with the sum of to the contents of a base register (BX or
BP) and index register (SI or DI), in a default segment.
Example: MOV AX, 50 [BX] [SI]
In Nvis 5586A Register relative, Based indexed and Relative based indexed addressing
modes are only supported by entering opcode.
Summary of Contents for 5586A
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Page 48: ...Nvis 5586A Nvis Technologies Pvt Ltd 48 Diagram of module RESET power Instruction Set Note...
